Field
One or more embodiments relate to a positive electrode active material, a method of manufacturing the positive electrode active material, and a lithium battery employing the positive electrode active material.
Description of the Related Technology
A lithium secondary battery using an organic electrolyte solution or a polymer electrolyte solution is a battery having high energy density due to the lithium secondary battery having a high discharge voltage equal to or higher than twice that of a battery using an alkali aqueous solution.
Some lithium secondary batteries are manufactured by using a material, in which lithium ions are intercalatable and deintercalatable, as a negative electrode and a positive electrode, and charging an organic electrolyte solution or a polymer electrolyte solution between the negative electrode and the positive electrode. Electric energy is generated according to an oxidation reaction and a reduction reaction where the lithium ions are intercalated into the positive electrode and deintercalated from the negative electrode.
Some lithium secondary batteries use lithium cobalt oxide (LiCoO2) as a positive electrode active material of the lithium secondary battery. However, manufacturing costs of the LiCoO2 are high, and it is difficult to reliably obtain LiCoO2. Some lithium secondary batteries have replaced cobalt using nickel and/or manganese in positive electrode active materials.
Positive electrode active materials including a nickel-based complex oxide are being developed for its low price, high capacity, and high voltage. However, these materials compared to the LiCoO2 are structurally unstable due to a large amount of deintercalated lithium ions during charging, have a capacity that is relatively easily deteriorated through charging and discharging, and have relatively weak thermal stability due to a reaction with an electrolyte solution. The present embodiments overcome the above problems as well as provide additional advantages.